Versnelling als gevolg van de zwaartekracht op aarde

An object is considered to be free-falling when the only force acting on it is the Earth's gravitational force. The acceleration of such a free-falling object is called acceleration due to gravity, denoted by g.

According to Newton's second law of motion, the magnitude of the force acting on the object is equal to its mass times its acceleration. It is also known as the object's weight.

Equating mg with the gravitational force equation, the acceleration due to gravity of the object can be expressed as the product of the gravitational constant and the Earth's mass, divided by the square of its distance from the Earth's center.

The average measured value of g close to the Earth’s surface is 9.8 m/s². Since g is independent of the object's mass, all masses near the Earth's surface free-fall with the same acceleration.

Therefore, substituting the values of acceleration due to gravity, the gravitational constant, and the distance as the Earth's radius, the Earth’s mass is estimated to be 5.97 × 10²⁴ kilograms.